Devices for expressing human breastmilk are well known. Manually or electrically operated vacuum pumps are connected directly or via vacuum lines to a breastshield, which is used to receive a part of the mother's breast including the nipple.
WO 2008/057218 discloses a breastpump with a vacuum pump, a vacuum line, a base, and a funnel-shaped and stiff breastshield that can be secured on this base. The vacuum line connects the vacuum pump to the base. In order to protect the vacuum line and the vacuum pump from contamination, a barrier in the form of a large-surface membrane is arranged in the base. This membrane is arranged in a pump chamber, in which the under-pressure generated by the pump unit is transferred to the other side of the membrane.
WO 2011/037841 likewise describes a breastpump with a base part, to which it is possible to connect a funnel-shaped and stiff breastshield, a vacuum line for connection to the vacuum pump, and a milk collection container. The base part likewise has a membrane in order to protect the vacuum line.
U.S. Pat. No. 7,223,255 and WO 2008/137678 disclose so-called hands-free breast pumps, which can be worn under the bra. The breast interface, which is placed sealingly on the mother's breast, serves at the same time as a membrane of the vacuum pump. That is to say, the pump chamber of the vacuum pump is formed between the soft breast interface and the mother's breast.
U.S. Pat. No. 6,379,327 discloses another hands-free breastpump. Here, a small breastshield is arranged in the bra. From this breastshield, a vacuum line leads to a vacuum pump unit and a milk line leads to a milk collection container. Vacuum pump unit and milk collection container are arranged in a strap, which the mother wears around her waist.
In US 2008/0262420, a flexible bag for collecting the milk is secured on a stiff breastshield, and both are worn in the bra. A vacuum line opening out in the upper area of the breastshield leads to a vacuum pump worn in a strap.
U.S. Pat. No. 6,440,100 also discloses a hands-free breastpump. Here too, a vacuum line leads from a breastshield to a vacuum pump. This line is at the same time used as a milk line.
US 2008/0039781 relates to a support device for stiff breastshields, wherein the support device can be secured on the bra.
U.S. Pat. No. 4,270,538 discloses a breastshield designed to catch a spontaneous flow of breastmilk. The breastshield has a soft breast interface and, connected to the latter, a cap into which the milk can flow.
WO 2011/035448 discloses a breastpump for expressing human breastmilk, in which a vacuum line is used at the same time as a milk line and in which a membrane of a diaphragm vacuum pump serves as media separator.